The radiative decay Λ0b → Λ0γ is observed for the first time using a data sample of proton-proton collisions corresponding to an integrated luminosity of 1.7 fb−1 collected by the LHCb experiment at a center-of-mass energy of 13 TeV. Its branching fraction is measured to be B(Λ0b → Λ0γ ) = (7.1 ± 1.5 ± 0.6 ± 0.7) × 10−6, where the quoted uncertainties are statistical, systematic and systematic from external inputs, respectively. A time-dependent analysis of the B0s → ϕ γ decay rate is performed to determine the CP-violating observables Sϕ γ and Cϕ γ, and the mixing-induced observable Aϕ∆γ. The measurement is based on a sample of p p collision data recorded with the LHCb detector, corresponding to an integrated luminosity of 3 fb−1 at center-of-mass energies of 7 and 8 TeV. The measured values are Sϕ γ = 0.43 ± 0.30 ± 0.11, Cϕ γ = 0.11 ± 0.29 ± 0.11, Aϕ∆γ = −0.67 +−003741 ±0.17, where the first uncertainty is statistical and the second systematic. The results are consistent with the Standard Model predictions.
|Журнал||Proceedings of Science|
|Состояние||Опубликовано - 1 янв 2019|
|Событие||18th International Conference on B-Physics at Frontier Machines, BEAUTY 2019 - Ljubljana, Словения|
Продолжительность: 29 сен 2019 → 4 окт 2019